<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>数组的</title>
</head>
<body>
    <script>
        //准备一个数组
        var arr=[100,200,300,400,500]
        //输出数组
        console.log(arr)

        //书写循环
        for(var i=0;i<arr.length;i++){
            //输出循环控制变量
            console.log(arr[i])
        }
    </script>
    <!-- 
    循环过程
    i为0 console.log(arr[0])
    i为1 console.log(arr[1])
    i为2 console.log(arr[2])
    i为3 console.log(arr[3])
    i为4 console.log(arr[4])
    -->
</body>
</html>